A rotary blade (A1) is provided with: a holding member (100) which is mounted to the rotary blade mounting shaft (14) of a mower and which is rotated a cord-like cutting member (4a) which has a base end side held by the holding member (100) and which has a front end side extended radially outward a guide member (200) which is rotatable below and relative to the holding member (100) about the rotation axis of the guide member (200) and recesses (240) which are provided in the outer periphery of the guide member (200) and which are recessed radially inward of the guide member (200). Each of the recesses (240) includes: a bottom section (241) a first sloped section (242) which continues from the bottom section (241) to the leading side of the holding member (100) in the direction of rotation thereof and a second sloped section (243) which continues from the bottom section (241) to the trailing side of the holding member (100) in the direction of rotation thereof. The first tilt angle (θ1) of the first sloped section (242) relative to the radial direction (r) of the guide member (200) is greater than the second tilt angle (θ2) of the second sloped section (243) relative to the radial direction (r) of the guide member (200).Linvention concerne une lame rotative (A1) pourvue : dun élément de retenue (100) qui est monté sur larbre de montage (14) de lame rotative dune faucheuse et qui est amené en rotation dun élément de coupe (4a) du type câble présentant un côté dextrémité de base retenu par lélément de retenue (100) et présentant un côté dextrémité avant sétendant radialement vers lextérieur dun élément de guidage (200) pouvant être amené en rotation sous lélément de retenue (100) et par rapport à celui-ci autour de laxe de rotation de lélément de guidage (200) et dévidements (240) ménagés dans la périphérie extérieure de lélément de guidage (200) et évidés radialement vers lintérieur de lélément de guidage (200). Chacun des évidements (240) comprend : une section in
